Railway signaling system



P 13, 1932- F. KRUCKENBERG ET AL 1,377,245

RAILWAY SIGNALING SYSTEM Filed April 30, 1928 3 Sheets-Sheet 1 p 13, F. KRUCKENBERG ET AL 1,877,245

RAILWAY SIGNALING SYSTEM Filed April so. 1928 s Sheets-Sheet 2 Sept. 13, 1932.

F. KRUCKENBERG ET AL RAILWAY SIGNALING SYSTEM 5 Sheets-Sheet 3 Filed April 30, 1928 Fig, 6

Fly. .5

H important result of theoreticallyreducing the l Patented Sept. 13, 1932 UNETQEDISTATES' PATENT :FFICE FRANZ KRUCKENBERG AND FRITZ HEYNIElR, OF HEIDELBERG, GERMANY; SAID HEYNER ASSIGNOR TO SAID KRUCKENBERG RAILWAY SIGNALING SYSTEM Application filed April v30, 1928, Serial No. 274,089, and in Germany May'5, 1927.

The new signaling system, which is designed for use on a railway operating at hlgh speeds up to 100 metres per second, has the space transport sequence, that is, the distance between two succeeding transports to the braking distance and thus permits the time sequence to be reduced to the very lowest possible figure. The basis of the railway signaling systems at present in use is that as long as one transport is within a given section,the so-called block section, the following transport must not enter this section. If the block sections are made equal tothe braking distance, the smallest possible space interval between transports for two-transports running at full speed i s given by a length equal to twice the braking distance plus the necessary safety distance and the greatest train length. If

this be compared with the space interval permitted by the invention, the numerical value of the advantage of reducing the space interval to one braking distance, that is to a fraction less than half that necessary with existing signaling systems, will be seen.

Shortly stated the means by which this re sult is obtained consist in that the necessary brak ng distance is shown at every instant to the rear of the forwardly proceeding-vehicle by a suitable signal system. Accordingly, in the simplest embodiment,behind each individual moving transport is what may be called a moving signal train of the length of a braking section which alters'nthe normal condition of the signal system-the all clear position of the signals-over its whole length. The end of this signal train may be indicated by a stop signal, which is always located close behind the leading transport, while the beginning may be marked by a preliminary signal which moves at a predetermined distance.

behind the stop signal. In normal or'uninterrupted traffic the following transport runs close behind the preliminary signal. If, however, the leading transport meets with some d fficulty (comes to rest or the like), the following transport will pass thepreliminary signal and can no longer observe it. This forms the notice for the driver to brake. If he then brakes properly he brings the transport to rest in good time before the end of the braking section, that is before reaching the halt signal.

The abovedescribed theoretically continuf 's ous signal train would involve sucha large number of signals and controlling devices 1 that the practical carrying out of this system would be impossible. For practical operation,therefore,' according tothe invention an intermittent or' step by step following up by the signal train is provided, that is the braking section is sub-divided by the arrangement of the signaling means. The signal train then'follows in steps by the amount of one ing transport and a preliminary signal which indicates the beginning of thebraking sect1on and moves closely before the following transport, there is no possibility of giving the driver any'indi'cationof his relative position when he isbetween the two signals.

To avoid this disadvantage, the leading transport is followed by a signal train not only with signals at its beginning and end,

but with signals at its subdivision points also. These signals are different from the all clear, preliminary and stop signals so that from their character the driver can judge I the distance from the transport in front. 5

Withthe highest speeds aimed at,the use of point form signals, as for example single lamps, is impossible. They wouldnot act on the perception of the driver for a sufii-i cient time, particularly when atmospheric influences (fog, rain and so forth) introduce].

difliculties. In the new system therefore not point form, but to a certain extent line form signals such as tubular incandescent lamps, or elongated gaseous conduction lamps are provided. Both the normal signal indica tion and the signal train comprise a close sequenceof individual signals which appear as a substantially continuous signal to the passing driver.

In the operation of the new system optical signals electrically controlled maybe used in various forms. The braking section is divided into several, for example four, subdivisions. The signal train comprises a sequence of coloured lamps, the subdivision immediately behind the leading transport consisting of a sequence of red lamps. The'two following subdivisions respectively comprise orange and dark yellow lamps. The fourth subdivision at the commencement of the train comprises yellow signal lamps. Behind this. the signal lamps can have the normal indicating. colour say greenfi. Advantageously, howeveig this last subdivision; is indicated, for instance, by white preparing or warning lamps which indicate to the driver that the "braking section commences with the next subdivision. In this 'case the addition for re:

action time, that is the time elapsing between t the perception of the signal to brake and the application of the brakes, to the braking sec-' tion, can be considerably reduced, which is advantageous in obtaining the lowest time sequence of the transports.

The invention is further described with reference to the accompanying drawings, in :which- 7 Figs. 1 and 2 are circuit diagrams showing av signaling system constructed according to the invention, 7

Figs. 3 and 4 are circuit diagrams show ing portions of the signaling circuit with the switches shown in their positions during certain stages of the operation, and

Figs. 5 and 6 are views of portions of a signaling circuit, showing additional switches which are employed in certain cases.

Referring first to Figure 1 thefigure eX- tends overseven times the length of a signal group, or subdivision of a braking section, the subdivisions being lettered in order from a to g, since'each of the subdivisions is similar to every other subdivision, the switch mechanisms In certain of the subdivisions havebeen omitted and have been indicated' merely by a rectangle. At each subdivisional point is a set of siX differently coloured signal'lamp groups here represented by single lamps. 61 is red, 60 orange, 59 dark yellow and 58 yellow, which four groups limit the full braking section. 57 is white and-serves as a warning or preparing signal "and 56 is green indicating all clear. For the automz'tticswitchingof the signal lamps, magnetic switches in conjunction with rail contacts actuated by the transports have been chosen by way of example. The magnetic switches and rail contacts are included in a signal current circuit S, the signal lamps a lamp current circuit An emergency circuit N, as can easily be seen, serves to setthe'whole signal systemat danger. .In the normal all clear condition of the system all the magnetic I switches are in the attracted position.

The switching operations can be followed by reference to Figures 1 and 2. If a vehicle A is in the position shown for example in Fig ure 1, that is in front of the rail contact of the subdivision point 9, the switched in green lamp 56 indicates all clear to the driver, since the armatures belonging to the magnet coils 51-55; are all attracted. When vehicle A runs on to the rail contact 50, then as shown in Figure 2 for the subdivision g, the c1rcuit containing the field coils 5155 is short circuited over the contact 50, all the armathe red lamp 611 is switched in over the contact 62 (Figure 2 subdivision g) the vehicle A is therefore covered. The signalzposition Y in subdivisions h and the succeeding groups (not shown) remainsunchanged. This continues for the further travel of the vehicle A until it reaches the neXt contact (not shown) and again short circuits the corresponding field windings. The'armatures are retracted, the green lamp 56 is cut out and the red lamp 61 switched in. Thevehicle A-is now covered on the next subdivisional section by the respective red lamp 61. In the example the si nal train which the vehicle A so to spear draws after itself, is as long as one braking section, subdivided into four. If the above described clearing of the signals is to be provided, at this point in the subdivisional section 6 (Figure 1) the respective orange lamps 60 must be switched in in place of the red group 61. From Figure 1 it will be seen that this operation in fact takes place. In consequence of the closure of contact (Figure 1 subdivision 9 )a circuit is closed. From +S (Figure 1, a current can flow over winding 55, switch 63, leads 64 and 65, rail contact 50 back to S in the subdivisional section 9. In this way the armature of winding is attracted (as seen in Figure 1 subdivision 6) and switches in theorange lamp in subdino vision 0 through switch 62.

On further travel of the vehicle A the same switching operation is repeated. The green group 56 is cut out and the red group 61 switched in. The closing of the next rail contact 50, F ig. 1 closes a further circuit. From +5 in section 6, Fig. 1 a current flows over winding 54, switches 66 and 67, leads 68, V V

69, 64, and rail contact 50 in section 9 back to S. The sections (Z, c, b, and a are eneris covered by a complete signal train. In the 125 subdivisional sections f, e, (Z, 0, respectively the red, orange, dark yellow and yellow lamps I 61, 60, 59 and 58 are switched in. In section g the normal signal indication exists since the green lamp 56 is switched in. In?) the white warninglanip 57 is switched in and in urthere is again the normal indlcation by the green lamp56. or v ,7

The described switching-sequence repeats itself continuously in regular operation.

If for any reason (mishap, stop signal or the like) the vehicle A comes to a standstill innthe-position. shown in Figure 1, a following vehicle (not shown) can still run at full speed to the end of the subdivision Z) Figure 1) covered by the white warning lamps andin doing so will efiect the above described switching operations behind itself. The driver knows thatyhe must brake from the appearance of the yellow lamps at the point 0 in order to bring hisvehicle to rest in good time at the endof thesubdivision fcovered by'the red lamp. l/Vhen the subdivision b is passed-and the respective contact closed the windings of the magnetic switches 5l55 traversed by current are short circuited and their armatures retracted; The white lamp 57 is cutout over switch. 62 and the redlamp switchedin. Further behind the above described switching operations take place. In the section a the orange lamp is switched in'in' place of the red group 61 and so forth. The switching operations-on further travel of the vehicle; are also similar to those above described. Finally the second vehicle as shown in Figure 2 will cometo rest'in the subdivisionalsection 7 covered by the red.

lamp 61. The Vehicle B itself is also protected by a complete signal train. vehicles can collect, see for example vehicle C of Figure 2. The-last vehicle isalways protectedby its signal train, V V i 1 I It is advantageous forthe end of the subdivisional section covered by'red lamps to be particularly indicated, so that theendof'the braking section is definitely shown to the driver. This can be effected for example by a particular configuration of the signal.

by a further section it. Three vehicles A, B, C, have moved into the positionindicated and the signals in the sections (Z, 6, 7 have been correspondingly switched. If now the vehicle A can move further, say through receiving the all clear signal, orthrough a break-;

down being rep aired, then on passing over the railcontact 50 of the section 9 Figure 2, the correspondin windings 51-55 will be short circuited. T e armaturesofithese windings will accordinglybe retracted. The. green lamp 56 will be cut out, the red lamp. 61 switched in. A current can then flow over switch 63 at f Figure 2, from +S (Figure 2 7), over winding 55, leads 64L and 65, rail con-f Further rinlcontradisti'nction totheifurther switchin operations with open seeti ns'Jbehind the ve icle A there is nowino possibility of further current flow over'the =closed rail contact 50 in section 9' Figure 2. In section 'e the switch with thelredllamp (SI-switched prevents "any flow of current and this "pre-' vents the switching in of the darkfyellow lamp 59in place of the redLlam-p 6i switched in owing to the position of the vehicle-B. In an analogous manner, lamp 600i group GQ of groupd is energized. In this way the switch ing out of the correctly connected orange lamp 60 is prevented and theyellow 58 isnot switched in as wouldbe theica'se if the sections behindvehicle A were not occupied. IOn

further movement of the vehicle A corresponding switching operations take place until finally the white: group '57 appears before the the vehicle B, which permits it to proceed, For the case where. the vehicles are starting from rest, ,the driver: ca'ni naturally'b'e given special instructi'onsgso.that he starts say as soon as the dark'yellow lamp group appears, so that the time intervallbetween-the subsequently starting vehicles may not be too great;

The exact time of starting. so that arpredetermined time sequence .of vehiclesfeanjbe maintained, can easily be-determined'for par.

'ticular lines, the highest 'speed, :brakingr'etardation, starting acceleration and: other such factors being .known.

Interruptions and faults of the most va ried kind are met by the invention as. follows:

The burning out. of individual 1 lamps is harmless since the lamp groups as suchiremain in existence and maintain-their signaling-functions. The failure of individual. magnetic switches to operate only causesiinternal interruptions within the-particular switch group. Assuming in-the course of i the switching operation the magnetic switch In Figure 2 the subdiv sional sections a c' I are omitted, but the figure is supplemented 52 (Figure 3) by the operationofwhichthe dark yellowlamp 59 should be switched "in, remains "out Then, since -the.switch .71 is not changed over, there is no possibility of) l the magnetic' switches 53, 54 and 55 being ac-v tuated. No lamp group therefore can ever be switched in'whichliesnearer in the sig-- nal train to the all clear lamps than the switched-in orange. On the contrary this'remainsunchanged until the rail contact '50 (Figure 3) isagain closed by a vehicle r-unning overit. Then the winding of theswit'clt 51, which-is still travers ed by current, is short v circuited and its armature isretracted, thus switching in the red group 61. This fault. is of no effect on the vehicle sequence, since 1 the neighbouring magnetic switch groups form a correctsignal trainup to the wrong ly indicatinggroup independently of the.

faulty switch. :Thereis simply aislight loss: I

of time, since the I driver will be unexpected ly obligedatofbrake' for one subdivisional brakingse'ction. Q I

,With sticking of the armature of one individual magnetic. switch no interference withthe signal trainis caused. It isidifl'e'rent when a number of neighbouring switches stick simultaneously. In this way a wrong lamp group is switched in by the respective magnetic switch group, this time of higher order than is correct In Figure it has .been assumed that the armatures of the magnetic switches 51, 52-, 53 have stuck simultaneously. In this case if for example the all clear condition previously existed and avehiclecloses the contact50, instead of the correct red' lamp .61, the incorrect yellow Elamp 58 would be switchedin, The driver would thus be permitted to brake less strong- 1y, This can only be dangerous if the leading vehicle" remains. stationary behind the faulty magnetic switch group and thefdriver of the following vehicle has not the presence of mind to apply the emergency brake.

.. The likelihood of'a collision in this case is extremely smallsince the following vehicle can vhave but a low speed," and the red tail lights of the leading vehicle. will be seen sufficiently early and certainly at such low speed. With the aid of a few. additional switch members it is possible to make the further switching of one magnetic switch group dependent on the-correct switching of the previous group, so that the increased in slstence of the drivers presence ac of mind can be avoided. I

A.'further interference in signaling can be caused by non-functioning of the rail con-.

' tacts; There then remains without change 7. contact being made and it shows a red light: continuously. If for some reason the supply of. current from the's'ource ceases, provision I can easily be made for asubstitute battery to 55.

. tioning aco'mplete signal trainbehind the non-funccontact, which compels the following vehicle to come to rest. In this case the vehicles must bedispatched over the sections with the faulty signals by specialemergency instructions It is fur- .ther'possible-bysimple measures (see Figurei5),namely by further switches 74 and 75 to, switch out the faulty rail contact. and if necessary faulty magnetic switch group until the fault has been remedied. This con-' dition can be indicated'to the driveriby a separate lamp .group which is illuminated simultaneously with the throwing over of the switches 7 at and 75. For the greatest security against such interruptions a plurality of par-' allel connected rail'contacts will be usedfas is shown in'the figures described above.

A further possibility of interruptionis the breakage of the conductors to the magnetic switches. If such a breakage occurs within the group itself, this group does not act on be switched in so. quickly that the magnetic unconditionally elongated illuminated member.

switcheswhich aregiven a certain inertia do not have time to release before the new supply is switched in. Only breakages of the current conductors cannot be provided for-in ad- Vance. Present day cable technique, however, makes it possible to install absolutelyreliable conductors. I i

All the lamps are fed, as already mentioned,

by a separate lamp feeding circuit (see Figure 6) By this provision all signals are set to halt (red light) if the lamp" circuit I is broken. As can be seen directly from Figure 12, in this case the armature 76 is retracted from magnet 77 and the-red lamp group N 61 is connected across the emergencycircuit +NN. Thissame emergencycircuit can ad vantageously also be used set the whole line or individual sect-ions to halt. A single switch 78 in such cases opens the lamp circuit." The armatures 7 6 of I all the magnetic switch groups are retracted and all the red lamp groups are fed by the emergency circuit, without the circuit being changed by further movement of the vehicles. If the lamp Circuit is again close'd'all lamps will be switched in in .accordancewith'the vehicle positions and the operation of theline can 'immediatef ly recommence in regular manner. 7

The magnetic switches in the example here; i

inbefore described, whichcan be actuated by direct or alternating currents, can naturally be replaced by other switching devices,-forexample by the known motor relays operating on the rotating field principle. lInlanother ioo 2. The invention as set forth in'claim wherein said displaying means comprises an elongated signal member extending longitudinally of the path of'travel of said vehicle.

3. Theinvention 'as set forth in claim '1, wherein said displaying means comprises an 4-. Ina signaling system for high speed extending substantially continuously along the entire path of travel of said vehicle for displaying a series of signal indications of different restrictive order with respect to. predetermined port-ions of thepath of said vehicle, of means actuated by the progress of said vehicle for displaying said indications successively and in serial order beginning with the most restrictive indication.

i 2 0 vehicle travel, the combination with means 5. In a sectionalized signaling system for high speed vehicle travel, the combination with means for displaying bands of light which extend substantially continuously along an entire section of the path or" travel of the vehicle of means actuated by the progress of a vehicle for controlling said display- I ing means in accordance with the position of said vehicle relatlve to said section.

6. In a sectionaliz'ed signaling system for high speed vehicle travel, the combination with means for displaying a series of signal indications which extend substantially continuously along an entire section of the path of travel each of said indications being of a different restriction order with respect to predetermined sections of the path, of means actuated by the progress of a vehicle past said section for controlling said displaying means to display said indications successively and in serial order beginning with the most restrictive indication.

7. The invention as set forth in claim 6, wherein said displaying means comprises a plurality of elongated parallel lamps of different appearance when energized extending along the path of the vehicle.

8. In a signaling system for high speed vehicle travel, the combination with means for displaying signals of difierent restrictive orders in the form of substantially continuous strips of light'each having distinctive coloration extending parallel to the path of travel of the vehicle of means actuated by the progress of the vehicle for controlling said displaying means to indicate the approximate position of said vehicle.

9. A signaling system for high speed vehicle trains comprising means for displaying a series of signal indications, each of said indications being of a difierent restrictive order with respect to predetermined portions of the path of said train and control means actuated by the progress of a train past and beyond said portions for displaying said indications successively and in serial order beginning with the most restrictive indication, said control means being divided into a plurality of sections related respectively to each of said portions of said train path and including means for rendering any of said sections inoperative independently of said other sections.

In testimony whereof we ailix our signatures.

FRANZ KRUGKENBERG. FRITZ HEYNER. 

